Radio Shack TRS-80 Technical Service Data Download

Page: 1 / 83

Summary of Contents for TRS-80

Page 1: ......

Page 2: ...19 Schematics CPU 2 3 30 31 32 33 Power Supply 5 28 Schematic Notes 9 Troubleshooting 7 8 9 IS Howard W Sams Co Inc 4300 West 62nd Street P O Box 7092 Indianapolis Indiana 46206 U S A The llliing of o...

Page 3: ...n Shunted 7 10 Open Open 8 9 Open Open 12V AND 5V ADJUSTMENT CPU AND KEYBOARD Connect the input of a DC voltmeter to pin 3 of Regulator IC Z2 Adjust the 12 0V Adjust Control Rl0 for 11 9V Connect the...

Page 4: ...NOT CENTERED ON MONITOR A Check the adjustment of the Horizontal Center Control R20 and Vertical Center Control R21 on the CPU Board see Horizontal and Vertical Centering section of Miscellaneous Ad...

Page 5: ...EXPANSION INTERFACE BOARD PRELIMINARY SERVICE CHECKS Continued CPU BOARD 19 7VAC MON ITOR VIDEO BOARD CASSETTE HOOIF lCATlOH COUOfTER IOARD HOR CENTER R21 VERT r CENTER 0 VERT Q SIZE rnD _ LEVEL IT R...

Page 6: ...k Basic mode To get back to the DOS from Disk Basic mode type IV CMD S and press the Enter key Any program in memory will be lost when leaving Basic mode by using CMD S DISK BASIC To load Disk Basic i...

Page 7: ...Continued PRELIMINARY SERVICE CHECKS Continued CE TER HORll R20 CR9 K1 CR10 CPU BOARD VIII CASSErE J3 Af1A f3C POWER V DEO POWtR SW TCH J2 Z29 J1 Sl r ROM SELECT SHU TS Z3 RAM SELECT SHU TS Z71 Z40 K...

Page 8: ...PI 3 Z20 5V AoJ R8 OV PI 3 Z21 JIi POWER J9 PRELIMINARY SERVICE CHECKS Continued G 0 OS DR EpaR J5 LINE PRI TER _j RT BUFFERED INTERFACE BUS PORT J3 tl 3 0 52 0 0 m f r z r m 0004 tl _ f eo o EXPANSI...

Page 9: ...Continued PRELIMINARY SERVICE CHECKS Continued CE TER HORll R20 CR9 K1 CR10 CPU BOARD VIII CASSErE J3 Af1A f3C POWER V DEO POWtR SW TCH J2 Z29 J1 Sl r ROM SELECT SHU TS Z3 RAM SELECT SHU TS Z71 Z40 K...

Page 10: ...s and contacts DISK DRIVES Clean the read write heads of the Disk Drives about once a month or after 100 hours usage Use only an approved head clean ing kit Handle carefully to preserve proper disk he...

Page 11: ...EXPANSION INTERFACE BOARD PRELIMINARY SERVICE CHECKS Continued CPU BOARD 19 7VAC MON ITOR VIDEO BOARD CASSETTE HOOIF lCATlOH COUOfTER IOARD HOR CENTER R21 VERT r CENTER 0 VERT Q SIZE rnD _ LEVEL IT R...

Page 12: ...ator MC1723CP MONITOR J 10 Z2 31 oo1 IC Regulator MC1723CP m Z3 2100041 Shunt ROM Select ITEM PART NO DESCRIPTION i Z13 3108009 IC RAM MB8116E XI _Cf thru 3108003 1 IC RAM F101 426973 Fuse 1A 250V Fas...

Page 13: ...I V 14 Z33 ROPl 20 Z34 ROPl B 20 HUX SH74LS32N 123 ZRD ZIflEQ 1 n Zl R ZIORO He I I ZRD I 4 t f I I 2 I R1B 5 0Vc o I 4700 I SH74LS32N I PART a 173 I m I I 5 0YCC I ll TO PIN 20 a ADDED ROPl P 1 1 6V...

Page 14: ...SI32N PART OF Z24 SH74LSI32N PART OF Z24 HCHOO18 PART OF Z2C R42 1M HCHOOl8 PART OF Z2C HCHOOIB PART OF Z2C CRS IH 4H8 R34 470K HCHOOl8 PART OF Z2C l 13 R200 10K 2 5 r NW 4 CR201 lH 4H8 CR200 L IH4H8...

Page 15: ...y will be lost when leaving Basic mode by using CMD S DISK BASIC To load Disk Basic into the Computer boot up on DOS In sert a diskette containing Disk Basic usually a part of the DOS diskette into Di...

Page 16: ...CIRCUITRACE OIl PART a 51 POWER J 118 I PART a 51 I POWER a F OH PIA 1 104 _ L r r r 1 2 PIA JIA h 1 4 1 I I CR8 A202 POIiER 5 lY 17 PTI 120VAC 400 00 I I I I I I I I PIA JIAYS IV L He 12 0 Vf _ He 2...

Page 17: ...1 YO _ 1 IYO I GNO OUTPUTS 61 1_Y _ 11Y1 8 GNO 4Q I 40 U 40 13 30 2 3 11 3 10 vee 16 ClOCK 9 Q Q Q ij vee 16 I m m fliPIFLOP TOP VIEW 511741 17511 SH7US367AH ClRP o1 qClR ClRP qClR 4Y 9 CK 4 r t CK C...

Page 18: ...stop check ROM AlB IC Z1 B RAM ICs Z13 thru Z20 by substitution Verify that the CPU Clock is operating properly by checking for a frequency of 10 6445MHz at pin 6 of IC Z42 If the clock is off freque...

Page 19: ...t and check that RAM IC by substitution NOTE No RAM IC is used for bit 6 Bit 6 is produced by comparing bits 5 and 7 with a NOR Gate IC Z30 If the pro gram indicates bit 6 is bad and bits 5 and 7 are...

Page 20: ...255 20 PRINT X X 30 OUT 255 0 GOTO 10 The number X that appears on the Monitor screen should be 255 when the 1kHz signal is injected at pin 4 of Connector J3 and 127 with no signal injected If the num...

Page 21: ...Z56 PIIIJ 1 CPU BOARD A Howard W Sam IUAiiiI f i3i Photo 10 D 3 0 2 cO men I 0 m D _en o CPU BOARD 23...

Page 22: ...Z8 Z42 Z43 Z25 Z44 P 1 P P 1 P P 1 PI 1 P 1 PI 1 PI 1 pI 1 Zll Z12 Z13 Z15 Z16 Z17 P 1 PI 1 PI 1 Z2 Z19 Z51 p PI 1 P 1 Z20 Z38 272 Z36 Z73 P PI 1 PI 1 PI 1 PI N 1 PI N 1 PI N 1 PI 1 Z39 Z22 Z23 255 2...

Page 23: ...22 23 24 25 1 26 27 28 29 30 A A B B C C D D E E tJ F F 3 0 2 cO G G mC r r C m H H 4 tJ _C CD 0 J J K K L L M M N N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 C...

Page 24: ...Z26 G 6 s C33 G 20 R26 0 3 Z27 G 7 O C34 G 21 R27 0 4 Z28 G 8 cO C35 H 4 R28 0 4 Z29 G 9 mUl C36 H 6 R29 C 4 Z30 G l0 I C37 H l1 R30 0 4 Z31 G 12 C38 H 25 R31 0 6 Z32 G 13 0 m C39 1 3 R32 E 2 235 G 1...

Page 25: ...5 OV C LEVEL II ROM BOARD A Howard W Sam iliiWiii f t3i Photo pl 1 ZlA PARTIAL KEYBOARD A Howord W Saml ilii ijiiiid3i Photo 14 pl r Z4A R1A...

Page 26: ...Q3 MJE29 GE 241 NTE196 ECG196 SK3054 196 WEP756 196 121 987 3 T1P29 4820004 GE 302 NTE291 ECG291 SK3440 291 WEP780 291 121 Z9047 TIP29A GE 302 NTE291 ECG291 SK3440 291 WEP780 291 121 Z9047 Q4 2N6594 4...

Page 27: ...0 NTE74LS20 ECG74 LS20 SK74LS20 HE 443 798 Z27 SN74LS175N 3102023 74LS175 NTE74LS175 ECG74LS175 SK74LS175 HE 443 752 Z28 SN74LS 174N 3102022 74LS 174 NTE74LS 174 ECG74LS 174 SK74LS174 HE 443 879 Z29 8...

Page 28: ...ECG4069 SK4069UB WEP4069 4069 905 260 Z58 SN74LS92N 3102016 ECG74LS92 Z59 SN74LS 175N 3102023 74LS 175 NTE74l S 175 ECG74LS 175 SK74LS 175 HE 443 752 Z60 SN74LS36 7AN 3102024 74LS367A NTE74LS367 ECG74...

Page 29: ...MENT DATA ITEM WORKMAN No RATING MFGR NEW TONE PART No PART No PART No R1A Res I stor Network ll R18 5 6 5 3W WW 4717003 1 Contains nine 4700 10 MISCELLANEOUS ITEM PART NAME MFGR NOTES No PART No CR1A...

Page 30: ...be on scope 7 Do not remove or install boards floppy disk drives printers or other peripherals with computer system AC power On 8 Do not use freon propelled sprays These can generate electrical charge...

Page 31: ...n the Monitor screen ROM SELECT SHUNT 23 Rom Select Shunt Z3 is set up in accordance to whether Level I or Level II Basic ROMs are installed Use the follow ing chart to determine which pins are shunte...

Page 32: ...22 23 24 25 1 26 27 28 29 30 A A B B C C D D E E tJ F F 3 0 2 cO G G mC r r C m H H 4 tJ _C CD 0 J J K K L L M M N N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 C...

Page 33: ...Z8 Z42 Z43 Z25 Z44 P 1 P P 1 P P 1 PI 1 P 1 PI 1 PI 1 pI 1 Zll Z12 Z13 Z15 Z16 Z17 P 1 PI 1 PI 1 Z2 Z19 Z51 p PI 1 P 1 Z20 Z38 272 Z36 Z73 P PI 1 PI 1 PI 1 PI N 1 PI N 1 PI N 1 PI 1 Z39 Z22 Z23 255 2...

Page 34: ...Z56 PIIIJ 1 CPU BOARD A Howard W Sam IUAiiiI f i3i Photo 10 D 3 0 2 cO men I 0 m D _en o CPU BOARD 23...

Page 35: ...C IC IC IC IC IC IC IC IC IC IC NO Z2C Z3A Z3B Z4 Z4A Z5 Z6 Z7 Z8 Z9 Z10 Zll Z12 Z13 1 H P P L P P P H L L L L P P 2 L H H L H P P L P H L L P P 3 L P H L P P P P P P L L P P 4 H H H P H P P H P P P P...

Page 36: ...C IC IC IC IC IC IC IC PIN IC PIN IC NO Z28 Z29 Z30 Z31 Z32 Z35 Z36 Z37 Z38 Z39 NO Z40 NO Z40 1 H P P H P P P H L L 1 P 21 P 2 P P L P P P H L L P 2 P 22 P 3 P P P P P P H L L P 3 P 23 H 4 P P H P P P...

Page 37: ...P P P H P P P P 2 P P L L P P P P L P P P 3 P P H P H H H P L P P P 4 P P P P P P P P P P P 5 P H P H P P P P P P H P P P 6 P L P L H P P P P P P P P 7 P L L L L P P P P P L P P 8 L P P P L L P P P L...

Page 38: ...1 YO _ 1 IYO I GNO OUTPUTS 61 1_Y _ 11Y1 8 GNO 4Q I 40 U 40 13 30 2 3 11 3 10 vee 16 ClOCK 9 Q Q Q ij vee 16 I m m fliPIFLOP TOP VIEW 511741 17511 SH7US367AH ClRP o1 qClR ClRP qClR 4Y 9 CK 4 r t CK C...

Page 39: ...CIRCUITRACE OIl PART a 51 POWER J 118 I PART a 51 I POWER a F OH PIA 1 104 _ L r r r 1 2 PIA JIA h 1 4 1 I I CR8 A202 POIiER 5 lY 17 PTI 120VAC 400 00 I I I I I I I I PIA JIAYS IV L He 12 0 Vf _ He 2...

Page 40: ...OLLER POIIER 1 1 REG I PACK r MTA I _ LINE TO LINE PRINTER r PRINTER CONTROlLER DATA I I _I EXPANSION RAM TO EXPANSION INTERFACE I 1J I TAPE TO CASSETTE TAPE Sill TCH TAPE RECORDER ErL J 0IIER REG CON...

Page 41: ...SI32N PART OF Z24 SH74LSI32N PART OF Z24 HCHOO18 PART OF Z2C R42 1M HCHOOl8 PART OF Z2C HCHOOIB PART OF Z2C CRS IH 4H8 R34 470K HCHOOl8 PART OF Z2C l 13 R200 10K 2 5 r NW 4 CR201 lH 4H8 CR200 L IH4H8...

Page 42: ...2ms 0 1 E A6 1 E A7 I i AB i 1 9 5H 4LSIIH PART a 166 11 m lf ll fi L2 h L t_ L4 m ___ LB 2V 2ms OV 2V 5ms OV O F NC o F NC o NC 5H 4LS04H PART a 19 CABLING HEAVY LINES REDUCE USE OF MULTIPLE LINE ItO...

Page 43: ...Howard W Sams CO Inc 4300 West 62nd Street P O Box 7092 Indianapolis Indiana 46206 U S A The listing of any available replocement port herein does not constitute in any cose Q recommendation warronty...

Page 44: ...510 R9 ISO l tvA R 1500 I l r 01 100 47 M s C24 I e 1I S3904 IOMS IIIIIIIIII II S S I 362 3 20bv I Q2 HOISE e 1f S3904 e If S3904 Q2 VIDeO MPlJT FILTER 01 VIDeO If QS VIDeO If I 53 _ _H I Cl 5Y II t _...

Page 45: ...I t I i 1101 lA I I Ql0l G HORIZ OUTPUT AC FUSE SA D Q9 VERT OUTPUT 9 5050 VERT SIZE VERT HOLD I I CR12 CR20 CR14 I o L CR17 i I CR9 CR19 Q3JR1 3 C lB b D SYNC CR10 Q7 0 KINE 0 QB 0 BLANKER VERT Q12...

Page 46: ...wiring in all areas 5 Components that indicate evidence of overheating should be replaced 6 WARNING The picture tube in thiS monitor employs integral implosion protection Replace with a tube of the s...

Page 47: ...ame safety characteristics as the recommended replacement part shown in the Parts List in this Data and its Sup plements and Bulletins may create shock fire or other hazards High voltage is maintained...

Page 48: ...MAIN BOARD 6 19 QV 16 2V 18 6V A A Howard W Saml li1 ii iii 3 Photo...

Page 49: ...l0 ml0 E 8 FB6 0 9 Q9 K 9 FB7 C 9 Qll 1 10 L2 K 2 Q12 F l0 Rl C 2 R2 E 2 R9 C 2 RUB K 7 1 2 3 5 R14 K l 4 6 7 8 9 10 11 R15 L 4 R16 L 4 A A R18 K 4 R19 K 2 en R20 K 3 R23 H l0 B B R24 B 9 en R25 F 8...

Page 50: ...87 CR107 M132 138173 GE 511 NTE552 ECG552 5K3130 WEPI72 506 103 287 CRl08 A8293O 6 1 2 02 362 3 GE 27 NTE171 ECG171 5K3201 171 WEP702 171 121 822 7362 3 141295 GE 27 NTE171 ECG171 SK3201 171 WEP702 17...

Page 51: ...G123AP SK3854 123AP WEP736 123A 121 Z9000A Q4 MPS3906 4822003 GE 82 NTE159 ECG159 SK3466 159 WEP621159 121 Z9003 2N3906 GE 82 NTE159 ECG159 SK3466 159 WEP62 159 121 Z9003 05 MPS3904 4822001 GE 123AP N...

Page 52: ...200V 10 139318 Cl02 36 N750 5 142023 Cl03 1 200V 10 242290 I I ITEM RATING MFGR No PART No Cl05 0015 1 2KV 141496 Cl08 180 143029 ClIO 1 125VAC 133343 Items numbers not listed are normally avaIlable a...

Page 53: ...2W Carbon FIlm 143031 HW5D6 22 2042 R61 3 3 5 1 2W Carbon FIlm 139324 HW3D3 22 2036 R77 10 5 1 2W Metal OxIde 830010 HW010 22 2048 R80 4 7 5 1 2W Carbon FIlm 140986 HW4D7 22 2040 Rl08 6800 5 1 2W Car...

Page 54: ...128456 FB6 FerrIte Bead 128456 FB7 FerrIte Bead 128456 FB10l FerrIte Bead 138013 L10l Ferr I te Bead 143038 P10l Power Cord 142453 AC Po Jar I zed SIOI SwItch 142639 Power VIOl CRT 12VBYP4 CRT 12VBNP4...

Page 55: ...A Howord W Sama iji ijMihD Photo VIDEO BOARD 13...

Page 56: ...Jnn 1 B C5 E 8 C6 E l1 C7 1 8 61 j IIII lI E j CRI C ll I Ql E 9 0 Q2 F 2 C f C F 4 0 J 4 _ r I Q3 a DD lIl1li1lilllllililllt JDD Q4 H 7 E Q5 H l1 Rl C 5 0 R2 C 9 3 R4 C 9 1 111J1I II flj R5 B 5 R6 0...

Page 57: ...D 0 2 0 mC r I r o m 4 D _C o A Howard W Sam tIliA 3i Photo MAIN BOARD 15...

Page 58: ...k Resistors R121 and R114 Check the voltages developed from Transformer T101 Check for 19 0V at junction of Resistors R9 and R61 16 2V at junction of Capacitor C44 and Electrolytic C39 18 6V at juncti...

Page 59: ...video with Computer connected to Connector P2 Check for 5 0V at pin 2 of IC Z1 This voltage is supplied by the Computer and if missing check Computer Check the Video Board by substitution or check Noi...

Page 60: ...l INF INF 500K INF 0 47K 12K 630 ITEM E B C ITEM E B C ITEM E B C Q2 200 516 1 5M Q8 1 6M 325K INF VIDEO BC II RD Q3 0 33 3959 Q9 1 6M 316K 5 Q1 182 47K 2109 Q4 6000 870K 1M Qll 57 INF 5501 1 Q2 INF I...

Page 61: ...ctangles appear in the alignment ad justment instructions Supply voltages maintained as shown at input Voltages measured with digital meter no signal Controls adjusted for normal operation Terminal id...

Page 62: ...l o o l C C C o m E CH1Ul Hlll Hl14 H1HS Cl01 R121 Cl12 _ Cl05 Cl07 CR107 Cl06 T101 FB101 l101 CR106 C10B Fl02 Fl01 Cll0 ClOg 0101 C113 II 131 31 I 13QOW 09 S U 40VHS OIQV...

Page 63: ...otective surface Remove four screws holding CRT to cabinet front and lift CRT out of cabinet Do not lift CRT by the neck SERVICING IN THE FIELD CRT IMPLOSION PROTECTION AND CLEANING Implosion protecti...

Page 64: ...Schematic Notes 15 Troubleshooting 14 15 I Howard W Sams Co Inc 1 4300 West 62nd Street P O Box 7092 Indianapolis Indiana 46206 U S A Th listing of any available r plocement pan Mr in does no1 Reprodu...

Page 65: ...0 rN He PART r l32 TRAHSCE VER NC 3 1 IV 3 WrIT He J2 4V loIV 3 i He i 1 V 3 W He r SN7 L SO H 7 1 1 i 1 2 rJ rL P f6 P p PART r l32 SN7 LSOOH 71 42 i 3 5lV 3 W h nr 0 I 1 P p 1 IV IP r 2 V 2 vhI9 f l...

Page 66: ...FOR TERMINAL GUIDES AND NOTES SEE PAGE 5 15 16 PHOTO CIRCUITRACE m SCHEIlATIC CIRCU TRACE D J 9 CR2 IlR B 1O I pgl J9 POWER SlPPlY 17 PTl r I I I20VAC I I 00 I I I 9 ItCl 0 9U6 PART OF ZI9 S OY He 3 2...

Page 67: ...11 9V 1 D 1 OV PI 1 _ Z47 PI 1 L Z48 F j D 1 Z36 JJ s 0 2 cO m J r t r n m JJ _ J Co o EXPANSION INTERFACE BOARD 4 A Howard W Sam lIIt III II t 3 Photo EXPANSION INTERFACE BOARD 17...

Page 68: ...218 DRIVER TOP VIEW OIOENT CR2 SIDE VIEW 1 01 I 1 I l U 12 II 1 10 a 219 TOP EW 1 1 I U I 11 II 1 7 217 227 221 n2 234 241 m 246 TOP lEW DO 238 TRANSCEIVER TOP VIEW SN74lS1S7 SELECT 1 SELECT vee 16 NP...

Page 69: ...H H H H 10 P P P P P P P P P P P P P P 11 P P P P P P P P P P P P P P 12 P P P P P P P P P P P P P P 13 P P P P P P P P P P P P P P 14 P P P P P P P P P P P P P P 15 H H H H H H H H H H H H H H 16 L...

Page 70: ...L H L H H H H 2 H 22 H 2 P P P H L L P P P 3 L 23 L 3 P L P H P P P P 4 H 24 P 4 P P P H P P P P P 5 P 25 H 5 P P P H P L P P P 6 P 26 H 6 P P P L H L P P P 7 27 L 7 L P P L L P P P P 8 28 L 8 H P P...

Page 71: ...12 0 13 0 14 R31 R32 R33 R34 R35 Yl ZI Z2 Z3 Z4 Z5 Z6 1 9 K 10 L 14 A 18 C 18 A 18 C 18 E 19 H 19 K 20 0 24 E 24 4 A Howord W Soms jli1Ji i W Photo A II R7 J l R19 Q l R8 K 1 R20 B 7 R9 K 2 R21 G 4 R...

Page 72: ...generate electrical charges sufficient to damage semiconductor devices 9 Periodically examine the AC power cord for damaged or cracked insulation 10 The computer system cabinet is equipped with vents...

Page 73: ...Z17 SN74LSOON 3102006 74LSOO NTE74LSOO ECG74LSOO SK74LSOO HE 443 728 Z18 MC75452P 3106002 NTE75452B ECG75452B HE 443 74 Z19 MC14049UB GE 4049 NTE4049 ECG4049 SK4049UB 221 Z9074 4049B GE 4049 NTE4049...

Page 74: ...3 74LS30 NTE74LS30 ECG74LS30 SK74LS30 HE 443 732 Z44 45 SN74LS244N 74LS244 NTE74LS244 ECG74LS244 SK74LS244 HE 443 791 Z46 SN74LS20N 74LS20 NTE74LS20 ECG74LS20 SK74LS20 HE 443 798 Z47 74LS 175PC 310202...

Page 75: ...ResIstor Network 2 R26 Res I stor Network 2 R27 Res I s tor Network 2 R35 5 6 5 3 11 WW 4717003 1 ContaIns four 4700 10 2 ContaIns four 33 10 MISCELLANEOUS ITEM PART NAME MFGR NOTES No PART No Kl Rel...

Page 76: ...12 0 13 0 14 R31 R32 R33 R34 R35 Yl ZI Z2 Z3 Z4 Z5 Z6 1 9 K 10 L 14 A 18 C 18 A 18 C 18 E 19 H 19 K 20 0 24 E 24 4 A Howord W Soms jli1Ji i W Photo A II R7 J l R19 Q l R8 K 1 R20 B 7 R9 K 2 R21 G 4 R...

Page 77: ...d have a width of 2 J s If the pulses are missing or the width is in correct check Capacitor C61 Resistors R23 and R24 and check Flip Flop IC Z33 by substitution 14 5V 5ms OV Figure 2 DISK DRIVE If th...

Page 78: ...trobe RD Read RD DATA Read Data STEP RIW Head Movement Pulse STROBE Data Strobe Clocking Pulse SYSRES System Reset TEST Test TRK 00 Track 0 WAIT Wait WR Write WR DATA Write Data WR PROT Write Protect...

Page 79: ...218 DRIVER TOP VIEW OIOENT CR2 SIDE VIEW 1 01 I 1 I l U 12 II 1 10 a 219 TOP EW 1 1 I U I 11 II 1 7 217 227 221 n2 234 241 m 246 TOP lEW DO 238 TRANSCEIVER TOP VIEW SN74lS1S7 SELECT 1 SELECT vee 16 NP...

Page 80: ...11 9V 1 D 1 OV PI 1 _ Z47 PI 1 L Z48 F j D 1 Z36 JJ s 0 2 cO m J r t r n m JJ _ J Co o EXPANSION INTERFACE BOARD 4 A Howard W Sam lIIt III II t 3 Photo EXPANSION INTERFACE BOARD 17...

Page 81: ...FOR TERMINAL GUIDES AND NOTES SEE PAGE 5 15 16 PHOTO CIRCUITRACE m SCHEIlATIC CIRCU TRACE D J 9 CR2 IlR B 1O I pgl J9 POWER SlPPlY 17 PTl r I I I20VAC I I 00 I I I 9 ItCl 0 9U6 PART OF ZI9 S OY He 3 2...

Page 82: ...4 6 CASSOUT 5 NC NC NC TO CASSETTE 2 NC NC NC NC NC NC 5 J NC NC 2 ctR __ J CLI _ oirt 1 P3 J8 r PARTOFdr O EN I l J P3 J8 f 7 5 5 PART r F 1 1 PW8 13of1 J6 2 2 Jl NC 2 Jl NC 4 Jl NC 6 Jl NC 8 TO CPU...

Page 83: ...is available at your Electronic Distributor If seal is broken nonreturnable 1 1 _ CSCS3 T I I ml Uti 01 _ lolll I I LOGIC on 1 Of 5111 SOl I 11i TROUBLESHOOTING MOCROO ROCU e l lCl Il oPlRA 10 1 0 _...

Search results

Summary of Contents for TRS-80

Reviews:

Related manuals for TRS-80

Brands by name

Popular brands

Radio Shack TRS-80, Technical Service Data

Search results

Summary of Contents for TRS-80

Reviews:

Related manuals for TRS-80

Brands by name

Popular brands